U.S. patent application number 14/278466 was filed with the patent office on 2015-11-19 for radiographic markers for partial penetration welded joints.
This patent application is currently assigned to SOLAR TURBINES INCORPORATED. The applicant listed for this patent is SOLAR TURBINES INCORPORATED. Invention is credited to Benjamin Richard Abraham, Jeffrey C. Brill, Daniel Patrick Weller.
Application Number | 20150328721 14/278466 |
Document ID | / |
Family ID | 54480404 |
Filed Date | 2015-11-19 |
United States Patent
Application |
20150328721 |
Kind Code |
A1 |
Abraham; Benjamin Richard ;
et al. |
November 19, 2015 |
RADIOGRAPHIC MARKERS FOR PARTIAL PENETRATION WELDED JOINTS
Abstract
A weldment member for a gas turbine engine including a forward
welding member and an aft welding member. The forward welding
member has an annular shape with a forward welding face formed at
one end. The forward welding face has a forward radiographic
marking hole formed therein. The aft welding member has an annular
shape with an aft welding face formed at one end. The aft welding
face has an aft radiographic marking hole formed therein. The
forward welding face is aligned with the aft welding face and the
forward radiographic marking hole is angularly offset from the aft
radiographic marking hole.
Inventors: |
Abraham; Benjamin Richard;
(San Diego, CA) ; Brill; Jeffrey C.; (Poway,
CA) ; Weller; Daniel Patrick; (San Diego,
CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOLAR TURBINES INCORPORATED |
San Diego |
CA |
US |
|
|
Assignee: |
SOLAR TURBINES INCORPORATED
San Diego
CA
|
Family ID: |
54480404 |
Appl. No.: |
14/278466 |
Filed: |
May 15, 2014 |
Current U.S.
Class: |
416/201R ;
219/121.14; 228/104 |
Current CPC
Class: |
B23P 2700/13 20130101;
B23K 31/125 20130101; F01D 5/063 20130101; B23K 15/0006 20130101;
B23P 15/008 20130101; F01D 1/20 20130101; F05D 2260/80 20130101;
G01N 23/02 20130101; Y10T 29/4932 20150115; B23K 11/02 20130101;
Y10T 29/49323 20150115; B23K 2101/001 20180801; F01D 5/06
20130101 |
International
Class: |
B23K 31/12 20060101
B23K031/12; F01D 1/20 20060101 F01D001/20; B23K 15/00 20060101
B23K015/00 |
Claims
1. A weldment member for a gas turbine engine comprising: a forward
welding member having an annular shape with a forward welding face
formed at one end of the annular shape, the forward welding face
having at least one forward radiographic marking hole formed
therein; and an aft welding member having an annular shape with an
aft welding face formed at one end of the annular shape, the aft
welding face having at least one aft radiographic marking hole
formed therein, wherein the forward welding face of the forward
welding member is aligned with the aft welding face of the aft
welding member and the at least one forward radiographic marking
hole is offset from the at least one aft radiographic marking hole
angularly.
2. The weldment member of claim 1, further comprising a plurality
of forward radiographic marking holes equally spaced around a
circumference of the forward welding member; a plurality of aft
radiographic marking holes equally spaced around a circumference of
the aft welding member; and wherein each of the forward
radiographic marking holes is offset angularly from each of the aft
radiographic marking holes.
3. The weldment member of claim 1, wherein the at least one forward
radiographic marking hole has a diameter less than or equal to 40
thousandths of an inch; and wherein the at least one aft
radiographic marking hole has a diameter less than or equal to 40
thousandths of an inch.
4. The weldment member of claim 1, wherein the at least one forward
radiographic marking hole has a hole depth greater than or equal to
50 thousandths of an inch and less than or equal to 70 thousandths
of an inch; and wherein the at least one aft radiographic marking
hole has a hole depth greater than or equal to 50 thousandths of an
inch and less than or equal to 70 thousandths of an inch.
5. The weldment member of claim 1, wherein a radially inner edge of
the at least one forward radiographic marking hole is disposed a
distance from an outer edge of the forward welding member, the
distance being equal to a weld penetration depth of the weldment
member; and wherein a radially inner edge of the at least one aft
radiographic marking hole is disposed a distance from an outer edge
of the aft welding member, the distance being equal to a weld
penetration depth of the weldment member.
6. The weldment member of claim 5, wherein the weld penetration
depth of the weldment member is 75% of a thickness of the weldment
member.
7. The weldment member of claim 1, wherein the at least one forward
radiographic marking hole is offset from the at least one aft
radiographic marking hole by a 45.degree. angle.
8. A gas turbine engine compressor rotor assembly, comprising: a
weldment member having a plurality of compressor disks, each
compressor disk comprising a forward welding member having an
annular shape with a forward welding face formed at one end of the
annular shape, the forward welding face having at least one forward
radiographic marking hole formed therein; and an aft welding member
having an annular shape with an aft welding face formed at one end
of the annular shape, the aft welding face having at least one aft
radiographic marking hole formed therein, wherein the forward
welding face of the forward welding member is aligned with the aft
welding face of the aft welding member and the at least one forward
radiographic marking hole is offset from the at least one aft
radiographic marking hole angularly; and wherein each of the
plurality of compressor disks including a plurality of rotor blade
slots; a plurality of compressor rotor blades, each located in one
of the rotor blade slots.
9. A gas turbine engine compressor rotor assembly of claim 8,
further comprising a plurality of forward radiographic marking
holes equally spaced around a circumference of each forward welding
member of each compressor disk; and a plurality of aft radiographic
marking holes equally spaced around a circumference of each aft
welding member of each compressor disk; and wherein each of the
forward radiographic marking holes is offset angularly from each of
the aft radiographic marking holes.
10. The gas turbine engine compressor rotor assembly of claim 8,
wherein the at least one forward radiographic marking hole has a
diameter less than or equal to 40 thousandths of an inch; and
wherein the at least one aft radiographic marking hole has a
diameter less than or equal to 40 thousandths of an inch.
11. The gas turbine engine compressor rotor assembly of claim 8,
wherein the at least one forward radiographic marking hole has a
hole depth greater than or equal to 50 thousandths of an inch and
less than or equal to 70 thousandths of an inch; and wherein the at
least one aft radiographic marking hole has a hole depth greater
than or equal to 50 thousandths of an inch and less than or equal
to 70 thousandths of an inch.
12. The gas turbine engine compressor rotor assembly of claim 8,
wherein a radially inner edge of the at least one forward
radiographic marking hole is disposed a distance from an outer edge
of the forward welding member, the distance being equal to a weld
penetration depth of the weldment member; and wherein a radially
inner edge of the at least one aft radiographic marking hole is
disposed a distance from an outer edge of the aft welding member,
the distance being equal to a weld penetration depth of the
weldment member.
13. The gas turbine engine compressor rotor assembly of claim 12,
wherein the weld penetration depth of the weldment member is 75% of
a thickness of the weldment member.
14. The gas turbine engine compressor rotor assembly of claim 8,
wherein the at least one forward radiographic marking hole is
offset from the at least one aft radiographic marking hole by a
45.degree. angle.
15. A gas turbine engine including the compressor rotor assembly of
claim 8.
16. A method of determining weld depth penetration in a weldment
member for a gas turbine engine, the method comprising: forming at
least one forward radiographic marking hole in a forward welding
face of a forward welding member; forming at least one aft
radiographic marking hole in an aft welding face of an aft welding
member; aligning the forward welding face of the forward welding
member with the aft welding face of the aft welding member; welding
the forward welding face of the forward welding member to the aft
welding face of the aft welding member using a penetration welding
process; radiographically imaging a portion of the weldment member
to determine if the at least one forward radiographic marking hole
and the at least one aft radiographic marking holes have been
obscured with welding material.
17. The method of claim 16, wherein the penetration welding process
is an electron-beam welding process.
18. The method of claim 16, wherein aligning the forward welding
face with the aft welding face comprises offsetting the at least
one forward radiographic marking hole from the aft radiographic
marking hole by an angle of 45.degree..
19. The method of claim 16, wherein the forming at least one
forward radiographic marking hole in the forward welding face of
the forward welding member comprises forming a plurality of forward
radiographic marking holes in the forward welding face, the
plurality of forward radiographic marking holes being equally
spaced around the circumference of the forward welding face; and
wherein the forming at least one aft radiographic marking hole in
the aft welding face of the aft welding member comprises forming a
plurality of aft radiographic marking holes in the aft welding
face, the plurality of aft radiographic marking holes being equally
spaced around the circumference of the aft welding face.
20. The method of claim 16, wherein the forming at least one
forward radiographic marking hole in the forward welding face of
the forward welding member comprises forming a radially inner edge
of the at least one forward radiographic marking hole a distance
from an outer edge of the forward welding member, the distance
being equal to a weld penetration depth of the weldment member; and
wherein the forming at least one aft radiographic marking hole in
the aft welding face of the aft welding member comprises forming a
radially inner edge of the at least one aft radiographic marking
hole a distance from an outer edge of the aft welding member, the
distance being equal to a weld penetration depth of the weldment
member.
Description
TECHNICAL FIELD
[0001] The present disclosure generally pertains to gas turbine
engines, and is more particularly directed toward gas turbine
engine compressor rotor assembly weldment member with radiographic
markers in partial penetration welded joints.
BACKGROUND
[0002] Gas turbine engines include compressors, and turbine
sections formed by welding together disks. In particular, groups of
metallic disks are welded together to form weldment members to
which turbine blades can be attached. In order to maintain quality
control, the welds between adjacent metallic disks may be inspected
using radiographic imaging processes to determine weld penetration
depth.
[0003] U.S. Pat. No. 3,974,381, to Rohrle et al., discloses a
welding method and apparatus for detecting the penetration depth of
an electron beam weld, in which X-rays which occur are guided
through several plates of an absorption device to a ray receiver.
The plates comprise a plurality of bores of equal diameter, which
are arranged in their position to one another in such a way that
the center lines of corresponding bores on the same level are in
exact alignment. The ray receiver, absorption device and work piece
are aligned in parallel with one another and are coordinated to one
another in height.
[0004] The present disclosure is directed toward overcoming one or
more of the problems discovered by the inventors.
SUMMARY OF THE DISCLOSURE
[0005] A weldment member for a gas turbine engine is disclosed. The
weldment member includes a forward welding member and an aft
welding member. The forward welding member has an annular shape
with a forward welding face formed at one end. The forward welding
face has at least one forward radiographic marking hole formed
therein. The aft welding member has an annular shape with an aft
welding face formed at one end. The aft welding face has at least
one aft radiographic marking hole formed therein. The forward
welding face is aligned with the aft welding face and the at least
one forward radiographic marking hole is angularly offset from the
at least one aft radiographic marking hole.
[0006] A gas turbine engine compressor rotor assembly is also
disclosed. The gas turbine engine compressor rotor assembly
includes a weldment member and a plurality of compressor rotor
blades. The weldment member has a plurality of compressor disks.
Each of the plurality of compressor disks includes a forward
welding member and an aft welding member. The forward welding
member has an annular shape with a forward welding face formed at
one end. The forward welding face has at least one forward
radiographic marking hole formed therein. The aft welding member
has an annular shape with an aft welding face formed at one end.
The aft welding face has at least one aft radiographic marking hole
formed therein. The forward welding face is aligned with the aft
welding face and the at least one forward radiographic marking hole
is angularly offset from the at least one aft radiographic marking
hole. Each of the plurality of compressor disks also includes a
plurality of rotor blade slots. The plurality of compressor rotor
blades are each located in one of the rotor blade slots.
[0007] A method of determining weld depth penetration in a weldment
member of a gas turbine engine is also disclosed. The method
includes forming at least one forward radiographic marking hole in
a forward welding face of a forward welding member. The method also
includes forming at least one aft radiographic marking hole in an
aft welding face of an aft welding member. The method also includes
aligning the forward welding face of the forward welding member
with the aft welding face of the aft welding member. The method
further includes welding the forward welding face of the forward
welding member to the aft welding face of the aft welding member
using a penetration welding process. The method additionally
includes radiographically imaging a portion of the weldment member
to determine if the at least one forward radiographic marking hole
and the at least one aft radiographic marking holes have been
obscured with welding material.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a schematic illustration of an exemplary gas
turbine engine.
[0009] FIG. 2 is a perspective view of the compressor rotor
assembly of the gas turbine engine of FIG. 1.
[0010] FIG. 3 is a cross-sectional view of a portion of the
weldment of the compressor rotor assembly of FIG. 2.
[0011] FIG. 4 is a cross-sectional view of an un-welded joint
between a forward welding member and an adjacent aft welding member
of the portion of the weldment of FIG. 3 taken along line
VI-VI.
[0012] FIG. 5 is another cross-sectional view of the un-welded
joint between the forward welding member and the adjacent aft
welding member of the portion of weldment of FIG. 4 taken along
line V-V.
[0013] FIG. 6 is an end view of a welding face of one of the
welding members of the portion of the weldment of FIG. 3.
[0014] FIG. 7 is an enlarged view of a portion of the welding face
of the welding member of FIG. 6.
[0015] FIG. 8 is another cross-sectional view of a welded joint
between the forward welding member and the adjacent aft welding
member adjacent welding members of the portion of weldment of FIG.
4 taken along line V-V.
[0016] FIG. 9 is a flowchart of a method for determining weld depth
penetration in a weldment member for a gas turbine engine.
DETAILED DESCRIPTION
[0017] The systems and methods disclosed herein include a gas
turbine engine compressor rotor assembly with marking holes
defining a weld line during radiographic inspection of the weld. In
embodiments, the compressor rotor assembly includes weldments
having forward and aft welding members with the marking holes
formed in the welding faces thereof. The marking holes of the
forward welding member may be offset from marking holes of the aft
welding member during welding. After welding the one or more of the
marking holes may be partially or completed filled with welding
material.
[0018] FIG. 1 is a schematic illustration of an exemplary gas
turbine engine. Some of the surfaces and structures have been left
out or exaggerated (here and in other figures) for clarity and ease
of explanation. Also, the disclosure may reference a forward and an
aft direction. Generally, all references to "forward" and "aft" are
associated with the flow direction of primary air (air which is
used in the Brayton cycle, the thermodynamic basis for gas turbine
operation), unless specified otherwise. For example, forward is
"upstream" relative to primary air flow, and aft is "downstream"
relative to primary air flow.
[0019] In addition, the disclosure may generally reference a center
axis 95 of rotation of the gas turbine engine, which may be
generally defined by the longitudinal axis of its shaft 120
(supported by a plurality of bearing assemblies 150). The center
axis 95 may be common to or shared with various other engine
concentric components. All references to radial, axial, and
circumferential directions and measures refer to center axis 95,
unless specified otherwise, and terms such as "inner" and "outer"
generally indicate a lesser or greater radial distance from,
wherein a radial 96 may be in any direction perpendicular and
radiating outward from center axis 95.
[0020] A gas turbine engine 100 includes an inlet 110, a shaft 120,
a gas producer or "compressor" 200, a combustor 300, a turbine 400,
an exhaust 500, and a power output coupling 600. The gas turbine
engine 100 may have a single shaft or a dual shaft
configuration.
[0021] The compressor 200 includes a compressor rotor assembly 210,
compressor stationary vanes ("stators") 250, and inlet guide vanes
255. The compressor rotor assembly 210 mechanically couples to
shaft 120. As illustrated, the compressor rotor assembly 210 is an
axial flow rotor assembly. The compressor rotor assembly 210 may
include one or more weldments 211 coupled by interference fits and
dowel pins to one another, which may be coupled to the forward hub
213 (shown in FIG. 2) which also may be coupled by interference
fits or curvics. The weldment 211 each include one or more
compressor disk assemblies 220. Each compressor disk assembly 220
includes a compressor disk 221 (shown in FIGS. 2 and 3) that is
circumferentially populated with compressor rotor blades 229.
[0022] Stators 250 axially follow each of the compressor disk
assemblies 220. Each compressor disk assembly 220 paired with the
adjacent stators 250 that follow the compressor disk assembly 220
is considered a compressor stage. Compressor 200 includes multiple
compressor stages. Inlet guide vanes 255 axially precede the first
compressor stage.
[0023] The combustor 300 includes one or more injectors 310 and
includes one or more combustion chambers 390.
[0024] The turbine 400 includes a turbine rotor assembly 410 and
turbine nozzles 450. The turbine rotor assembly 410 mechanically
couples to the shaft 120. As illustrated, the turbine rotor
assembly 410 is an axial flow rotor assembly. The turbine rotor
assembly 410 includes one or more turbine disk assemblies 420. Each
turbine disk assembly 420 includes a turbine disk that is
circumferentially populated with turbine blades. Turbine nozzles
450 axially precede each of the turbine disk assemblies 420. Each
turbine disk assembly 420 paired with the adjacent turbine nozzles
450 that precede the turbine disk assembly 420 is considered a
turbine stage. Turbine 400 includes multiple turbine stages.
[0025] The exhaust 500 includes an exhaust diffuser 510 and an
exhaust collector 520.
[0026] FIG. 2 is a perspective view of the compressor rotor
assembly 210 of FIG. 1. The compressor rotor assembly 210 may
include compressor rotor blades 229. The compressor rotor blades
229 may be axially installed compressor rotor blades ("axial
blades"), circumferentially installed compressor rotor blades
("circumferential blades"), or a combination of axial blades and
circumferential blades. The Compressor rotor blade sizes may be
determined by the sizes of the compressor disks 221.
[0027] FIG. 3 is a cross-sectional view of a portion of the
weldment 211 of the compressor rotor assembly 210 of FIG. 2. The
weldment 211 includes multiple compressor disks 221. Each of the
compressor disks 221 may include a forward welding member 226 and
an aft welding member 225. The forward welding member 226 may have
an annular shape and may extend forward from each of the compressor
disk 221. The aft welding member 225 may have an annular shape and
may extend aft from the compressor disk 221. The aft welding member
225 of a compressor disk 221 of a first stage may be welded to the
forward welding member 226 of a compressor disk 221 of a subsequent
stage. Each subsequent compressor disk 221 may be welded to the
previous compressor disk 221 in a similar manner.
[0028] Each compressor disk 221 of the weldment 211 may include a
peripheral flange 235 forming one or more a rotor blade slots 236.
In some embodiments, the each rotor blade slot 236 may be either an
axial slot or a circumferential slot. One or more compressor rotor
blades 229 may be inserted into each of the rotor blade slots 236.
If the compressor disk 221 has one or more axial slots, one axial
blade may be inserted into each axial slot. If the compressor disk
221 has a circumferential slot, multiple circumferential blades may
be inserted into the circumferential slot. In the embodiment shown
in FIG. 3, five compressor disks 221 having rotor blade slots 236
that are axial slots. In other embodiments, the rotor blade slots
236 may be circumferential slots or a combination of axial and
circumferential slots.
[0029] FIG. 4 is a cross-sectional view of an un-welded joint 231
between a forward welding member 226 and an adjacent aft welding
member 225 of the portion of the weldment 211 of FIG. 3. The
cross-section is taken along line VI-VI of FIG. 3. The relative
size and/or distance between components may be exaggerated to aid
clarity.
[0030] As illustrated, the forward welding member 226 has a
generally annular shape with a forward welding face 234 formed at
one end. Similarly, the aft welding member 225 has a generally
annular shape with an aft welding face 233 formed at one end. The
forward welding face 234 of the forward welding member 226 contacts
the aft welding face 233 of the aft welding member 225 at the joint
231 between the forward welding member 226 and the aft welding
member 225.
[0031] The forward welding member 226 is illustrated having a
plurality of radiographic marking holes 230 formed in the forward
welding face 234. However, other embodiments may have only a single
radiographic marking hole 230 formed in the forward welding face
234. Radiographic marking holes 230 formed in the forward welding
face 234 may be referred to as forward radiographic marking holes.
In some embodiments, the diameter of these marking holes 230 may be
40 thousands of an inch. However, embodiments of the marking hole
may have larger or smaller diameters. Additionally, in some
embodiments, the depth of the marking hole may be in a range of
50-70 thousandths of an inch. However, other embodiments may have a
larger or a smaller hole depth.
[0032] The aft welding member 225 is also illustrated having a
radiographic marking hole 230 formed in the aft welding face 233.
However, other embodiments may have a plurality of radiographic
marking holes 230 formed in the aft welding face 233. Radiographic
marking holes 230 formed in the aft welding face 233 may be
referred to as aft radiographic marking holes. Again, in some
embodiments, the diameter of these marking holes 230 may be 40
thousands of an inch. However, embodiments of the marking hole may
have larger or smaller diameters. Further, in some embodiments, the
depth of the marking hole 230 may be in a range of 50-70
thousandths of an inch. However, other embodiments may have a
larger or a smaller hole depth.
[0033] FIG. 4 illustrates that the forward welding face 234 of the
forward welding member 226 is positioned against the aft welding
face 233 of the aft welding member 225 with the radiographic
marking holes 230 of the forward welding member 226 being angularly
offset from the radiographic marking holes 230 of the aft welding
member 225 with respect to the central axis 95 (shown in FIG. 1).
In some embodiments, the angular offset may be a 45.degree. angle.
In other embodiments, the angular offset may be a larger or smaller
angle.
[0034] FIG. 5 is another cross-sectional view of the un-welded
joint 231 between the forward welding member 226 and the adjacent
aft welding member 225 of the portion of weldment 211 of FIG. 4.
The cross-section is taken along line V-V through one of the
radiographic marking holes 230 of the forward welding member 226 of
FIG. 4. The relative size and/or distance between components may be
exaggerated to aid clarity.
[0035] In FIG. 5, only one radiographic marking hole 230 is visible
due to the section cut illustrated and other radiographic marking
holes 230 have been omitted for clarity. The radiographic marking
hole 230 is located a radial distance 232 below the outer edge or
circumference (upper side as illustrated in FIG. 5) of the aft
welding member 225. The radial distance 232 may be measured between
the outer edge or circumference of the aft welding member 225 and
radially inner edge of the radiographic marking hole 230 (lower
side of radiographic marking hole 230 as illustrated by reference
line 238 in FIG. 5) of the radiographic marking hole. In some
embodiments, the radial distance 232 may correspond to a weld
penetration depth used during welding of the welding members as
discussed below.
[0036] FIG. 5 also illustrates that a chamfered notch 237 may be
provided adjacent to the forward welding face 234 of the forward
welding member 226. Similarly, a chamfered notch 237 may also be
provided adjacent to the aft welding face 233 of the aft welding
member 225.
[0037] FIG. 6 is an end view of the aft welding face 233 of the aft
welding member 225 of the portion of the weldment of FIG. 3. FIG. 7
is an enlarged view of a portion of the aft welding face 233 of the
aft welding member 225 of FIG. 6. The forward welding face 234 of
the forward welding member 226 is structurally similarly to the aft
welding face 233 illustrated in FIGS. 6 and 7 and redundant
illustration of the forward welding face 234 of the forward welding
member 226 is therefore omitted.
[0038] In the embodiment of FIG. 6, eight radiographic marking
holes 230 are provided in the aft welding face 233 of the aft
welding member 225. However, in other embodiments, more or less
than eight radiographic marking holes 230 may be provided. For
example, four radiographic marking holes may be provided in the aft
welding face 233. Additionally, a similar number of radiographic
marking holes 230 may also be provided in the forward welding face
234.
[0039] As illustrated, the radiographic marking holes 230 are
positioned at equally spaced angular positions around a
circumference of the aft welding face 233. The geometric center of
each of the radiographic marking holes 230 is located at a common
radial position as illustrated by reference line 239. The
radiographic marking holes 230 are illustrated as having a circular
cross-section. However, the radiographic marking holes 230 are not
limited to this configuration and may have other shapes such as an
oval, a square, or any other shape that may be apparent to a person
of ordinary skill in the art.
[0040] Further as illustrated in FIG. 7, each radiographic marking
hole 230 is located a radial distance 232 below the radially outer
edge or circumference of the aft welding member 225. The radial
distance 232 may be measured between the outer edge or
circumference of the aft welding member 225 and radially inner edge
of the radiographic marking hole 230 (lower side of radiographic
marking hole 230 as illustrated by the reference line 238 in FIG.
5) of the radiographic marking hole. As mentioned above, the radial
distance 232 may correspond to a weld penetration depth used during
welding of the welding members as discussed below.
[0041] FIG. 8 is a cross-sectional view of the joint 231 between
the forward welding member 226 and the adjacent aft welding member
225 of the portion of weldment 211 shown in FIG. 4 after the joint
has been welded. FIG. 8 shows the same features illustrated in FIG.
5 discussed above and uses the same reference numerals for the same
components. As with FIG. 5, the cross-section is taken along line
V-V of FIG. 3.
[0042] A weld 700 has been formed between the forward welding
member 226 and the aft welding member 225. In some embodiments, the
weld 700 includes welding material that has flown into one of more
of the radiographic marking holes 230. In some embodiments, all of
the radiographic marking holes 230 may be completely filled by
welding material from the weld 700. However, in other embodiments,
only a few or even only one of the radiographic marking holes 230
may be completely filled and the remaining radiographic marking
holes 230 may be only partially filled. Further, in some
embodiments, one or more radiographic marking holes 230 may remain
completely unfilled by welding material from the weld 700.
INDUSTRIAL APPLICABILITY
[0043] Gas turbine engines may be suited for any number of
industrial applications such as various aspects of the oil and gas
industry (including transmission, gathering, storage, withdrawal,
and lifting of oil and natural gas), the power generation industry,
cogeneration, aerospace, and other transportation industries.
[0044] Referring to FIG. 1, a gas (typically air 10) enters the
inlet 110 as a "working fluid", and is compressed by the compressor
200. In the compressor 200, the working fluid is compressed in an
annular flow path 115 by the series of compressor disk assemblies
220. In particular, the air 10 is compressed in numbered "stages",
the stages being associated with each compressor disk assembly 220.
For example, "4th stage air" may be associated with the 4th
compressor disk assembly 220 in the downstream or "aft" direction,
going from the inlet 110 towards the exhaust 500). Likewise, each
turbine disk assembly 420 may be associated with a numbered
stage.
[0045] Once compressed air 10 leaves the compressor 200, it enters
the combustor 300, where it is diffused and fuel is added. Air 10
and fuel are injected into the combustion chamber 390 via injector
310 and combusted. Energy is extracted from the combustion reaction
via the turbine 400 by each stage of the series of turbine disk
assemblies 420. Exhaust gas 90 may then be diffused in exhaust
diffuser 510, collected and redirected. Exhaust gas 90 exits the
system via an exhaust collector 520 and may be further processed
(e.g., to reduce harmful emissions, and/or to recover heat from the
exhaust gas 90).
[0046] Gas turbine engines and other rotary machines include a
number of rotating elements rotating at high speeds and experience
high thermal and mechanical stresses. Therefore, the welds between
components, such as the forward welding member 226 and aft welding
member 225 of the compressor disks 221 of the weldment, are usually
inspected during assembly and at regular maintenance schedules to
detect flaws that may result in failure of the components during
operation.
[0047] As illustrated in FIGS. 3, 4, 5, 6, 7, and 8, the weldment
member 211 of the compressor rotor assembly 210 is formed by a
plurality of compressor disks 221. Each compressor disk 221 is
formed from a forward welding member 226 having a forward welding
face 234 and an aft welding member 225 having an aft welding face
233. During assembly of each compressor disk 221, the forward
welding face 234 is welded to the aft welding face 233. Typical
welding processes include, but are not limited to, electron-beam
welding process, laser-beam welding process, or any other narrow
beam, high energy welding process that may be apparent to a person
of ordinary skill in the art.
[0048] Embodiments of the present application include one or more
radiographic marking holes 230 in both the forward welding face 234
and the aft welding face 233 that can be used to determine weld
depth penetration during weld inspection.
[0049] FIG. 9 is a flowchart of a method 900 for inspecting the
weld 700 and determining weld depth penetration in a weldment
member 211 for a gas turbine engine 100. In step 905, at least one
radiographic marking hole 230 is formed in the forward welding face
234 of the forward welding member 226. The radiographic marking
hole 230 may be placed a radial distance 232 from the radially
outer edge or circumference of the forward welding member 226. The
radial distance 232 may be measured between the outer edge or
circumference of the forward welding member 226 and radially inner
edge of the radiographic marking hole 230 (lower side of
radiographic marking hole 230 as illustrated by the reference line
238 in FIG. 5).
[0050] The radiographic marking hole 230 may be formed by drilling,
milling, or other machining process that may be apparent to a
person of ordinary skill in the art. In some embodiments, the
radiographic marking hole 230 may be formed as a circular hole
having a diameter of 40 thousandths of an inch and hole depth in a
range of 50-70 thousands of an inch. In other embodiments, the
radiographic marking hole 230 may have a different shape or may
have larger or smaller dimensions as discussed above. However, if
the size or shape of the radiographic marking hole becomes too
large, the radiographic marking hole 230 may create a failure point
in the forward welding member 226 that could cause potential
failure during operation.
[0051] Similarly, in step 910, at least one radiographic marking
hole 230 is formed in the aft welding face 233 of the aft welding
member 225. The radiographic marking hole 230 may be placed a
radial distance 232 from the radially outer edge or circumference
of the aft welding member 225. The radial distance 232 may be
measured between the outer edge or circumference of the aft welding
member 225 and radially inner edge of the radiographic marking hole
230 (lower side of radiographic marking hole 230 as illustrated by
the reference line 238 in FIG. 5).
[0052] The radiographic marking hole 230 may be formed by drilling,
milling, or other machining process that may be apparent to a
person of ordinary skill in the art. In some embodiments, the
radiographic marking hole 230 may be formed as a circular hole
having a diameter of 40 thousandths of an inch and hole depth in a
range of 50-70 thousands of an inch. In other embodiments, the
radiographic marking hole 230 may have a different shape or may
have larger or smaller dimensions as discussed above. However, if
the size or shape of the radiographic marking hole 230 becomes too
large, the radiographic marking hole 230 may create a failure point
in the aft welding member 225 that could cause potential failure
during operation.
[0053] In step 915, the forward welding face 234 of the forward
welding member 226 is aligned to the aft welding face 233 of the
aft welding member 225. More specifically, the forward welding face
234 is aligned with the aft welding face 233 so that the one or
more radiographic marking holes 230 formed in the forward welding
face 234 is angularly offset from the one or more radiographic
marking holes 230 formed in the aft welding face 233. In some
embodiments, the angular offset may be 45.degree.. In some
embodiments, the angular offset may be more or less than
45.degree.. In some embodiments, the forward welding face 234 may
be manually aligned with the aft welding face 233 by a human. In
other embodiments, the forward welding face 234 may be
automatically aligned with the aft welding face 233 by an automated
assembly machine using machine vision.
[0054] After the forward welding face 234 is aligned with the aft
welding face 233 with the respective radiographic marking holes 230
angularly offset from each other in step 915, the forward welding
member 226 is welded to the aft welding member 225 along the joint
231 (illustrated in FIGS. 4 and 5) in step 920. The welding process
may be a penetration welding process and may include electron-beam
welding, laser-beam welding, or any other narrow beam, high energy
welding process that may be apparent to a person of ordinary skill
in the art. During the welding process, the energy intensity may be
set to a level to produce a specific amount of penetration by the
high-energy beam as is known in the art. For example, the energy
intensity may be set to produce a minimum penetration of 75% of the
thickness of the welding member. In some embodiments, the maximum
penetration may be up to 95%, and in some cases the maximum weld
penetration may be well below 95%.
[0055] In some embodiments, the minimum penetration set to be
produced during the welding may correspond to the radial distance
232 between the outer edge or circumference of the respective
welding member (i.e. forward welding member 226 and aft welding
member 225) and the radially inner edge of the radiographic marking
hole 230 (illustrated by the reference line 238 in FIG. 5). For
example, the radial distance 232 between the outer edge or
circumference of the welding member and the radially inner edge of
the radiographic marking hole 230 may correspond to 75% of the
thickness of the welding member if the energy intensity is to be
set to produce a minimum penetration of 75% of the thickness of the
welding member.
[0056] In step 925, after the forward welding member 226 has been
welded to the aft welding member 225, a portion of the weldment 211
around the weld 700 may be radiographically imaged. Specifically,
the weld 700 may be radiographically imaged by passing non-visible
electromagnetic radiation through the weld 700 from a generator on
one side of the weld 700 to a detector on an opposite side of the
weld 700. For example, the radiation generator may be placed on a
radially outer side of the weld 700 and the radiation detector may
be placed on a radially inner side of the weld 700. In some
embodiments, the radiographic imaging may produce still images used
to evaluate sections or portions of the weld 700. In other
embodiments, the radiographic imaging may produce video that may be
used to evaluate the entire weld 700 as the weldment 211 is rotated
relative to the radiation generator and radiation detector.
[0057] The type of non-visible electromagnetic radiation passed
through the weld is not particularly limited and may include X-ray
radiation, Gamma-Ray radiation, and any other form of radiation
that may be apparent to a person of ordinary skill in the art.
[0058] Using the radiographic images produced during the
radiographic imaging, the penetration depth and weld alignment can
be visually inspected. Specifically, the radiographic marking holes
230 on the forward welding face 234 side of the weld 700 and the
aft welding face 233 side of the weld 700 are generally visible on
the radiographic image if no welding material from the weld 700 has
flowed into the radiographic marking holes. As the radiographic
marking holes 230 are filled with welding material from the weld
700, the visibility of the radiographic marking hole 230 on the
radiographic image will diminish and may be completely lost if the
radiographic marking hole 230 is completely filled.
[0059] The weld penetration depth and weld alignment may be
determined to be within acceptable tolerances and deemed to be a
good weld if all or a majority of the radiographic marking holes
230 on the forward welding face 234 side of the weld 700 and the
aft welding face 233 have been completely or substantially obscured
by welding material flowing into the radiographic marking holes 230
from the weld 700. Conversely, if all or most of the radiographic
marking holes 230 are completely visible on the radiographic image
the weld penetration depth and/or weld alignment may be determined
to unacceptable and the weld 700 rejected. The specific number of
visible radiographic marking holes or the degree of visibility that
determines whether a weld is acceptable or rejected may vary
depending on the needed design parameters of the parts being welded
as may be apparent to a person of ordinary skill in the art. For
example, some weld design parameters may require a 100% fill rate
of the radiographic marking holes to be deemed an acceptable weld
in some embodiments. In other embodiments, a 95% fill rate, a 90%
fill rate, an 85% fill rate, etc. may be acceptable.
[0060] By providing a process to visually inspect the welds and
quantify levels of weld penetration, improved weld quality, and
reduced weld failure may be produced. As weld quality is improved,
and weld failure rates are reduced, product life may be extended
resulting in repair/replacement cost savings and reduced equipment
down time.
[0061] The preceding detailed description is merely exemplary in
nature and is not intended to limit the invention or the
application and uses of the invention. The described embodiments
are not limited to use in conjunction with a particular type of gas
turbine engine. Hence, although the present disclosure, for
convenience of explanation, depicts and describes a particular
forward welding member, a particular aft welding member, and
associated processes, it will be appreciated that other forward
welding members, aft welding members, and processes in accordance
with this disclosure can be implemented in various other compressor
rotor assemblies, configurations, and types of machines.
Furthermore, there is no intention to be bound by any theory
presented in the preceding background or detailed description. It
is also understood that the illustrations may include exaggerated
dimensions to better illustrate the referenced items shown, and are
not consider limiting unless expressly stated as such.
[0062] Additionally, the above discussed embodiments relate to
welding of compressor rotor disks of a weldment of a compressor
rotor assembly of a gas turbine engine. However, embodiments of the
present application are not limited to these components and may
also relate to other welded components of the gas turbine
engine.
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